Liquid crystal shutter device for color imaging on photosensitive medium

ABSTRACT

A liquid crystal shutter device is provided with a liquid crystal cell including a first substrate ( 1 ), a second substrate ( 21 ), and liquid crystal sandwiched therebetween, pixel electrodes ( 11, 12 ) which are signal electrodes and lead-out electrodes ( 15 ) provided on the first substrate ( 1 ), counter electrodes which are common electrodes facing the pixel electrodes, provided on the second substrate ( 21 ), and a plurality of pixel rows ( 200, 300, 400 ) which are composed of pixels ( 2, 3, 4,  etc.) formed by overlapped portions of the pixel electrodes and the counter electrodes, and the liquid crystal shutter device controls light applied to a photosensitive member continuously and relatively moving in a direction orthogonal to the pixel rows, in which the counter electrodes are provided separately for the respective pixel rows. Further, an RGB coupling electrode ( 46 ) for electrically connecting the counter electrodes of the respective pixel rows is preferably provided.

TECHNICAL FIELD

The invention relates to a liquid crystal shutter device which controlslight transmittance by electric signals for each pixel, and morespecifically, to a liquid crystal shutter device used in an opticalprinter which forms a color image on a photosensitive membercontinuously and relatively moving, by controlling light irradiation tothe photosensitive member.

BACKGROUND TECHNOLOGY

In recent years, video printers for printing out such an image on asheet as displayed on a display screen after digitalization are inwidespread use. The printing methods of the video printers includethermal method, ink-jet method, laser-beams scanning method, liquidcrystal shutter method, and so forth. Among others, the liquid crystalshutter method is closely watched in view of its suitability fordownsizing and weight saving.

The liquid crystal shutter method is a method for forming the image on aphotosensitive member continuously and relatively moving, by controllinglight irradiation to the photosensitive member with the use of a liquidcrystal shutter device which controls light transmittance for each of aplurality of pixels aligned in one or more line(s) by ON/OFF, that is,opening/closing, by applying or not applying voltages to a liquidcrystal layer. A printer employing the method is referred to as anoptical printer.

A printing method using such a liquid crystal shutter device forprinting out the image on a photosensitive paper using full range ofcolors is disclosed for example in JP, S62-134624, A. This method ischaracterized in that the liquid crystal shutter device and a whitelight source are used, in which a turret with color filters of red,blue, and green thereon is rotated by a motor to thereby selectivelyirradiate light from the light source as lights of red, green, or blueto the photosensitive paper via the liquid crystal shutter device, sothat a full-color image is formed on the photosensitive paper.

Also, in JP, H6-186581, A, a structure to be hereinafter described ispresented as one structure of the liquid crystal shutter device, inwhich pixel rows corresponding to the respective three light colors areprovided, where pixels composing the pixel rows are aligned in two linesfor each color in a direction orthogonal to a moving direction of thephotosensitive paper at same pitches as of a pixel size of the aligningdirection, each pixel of one of the two lines and that in the other linebeing arranged misaligning with each other by one pixel size inrespective aligning directions, and a lead-out electrode of each pixelbeing led out in the moving direction of the photosensitive paperthrough spaces between the pixels.

When configuring the optical printer using the liquid crystal shutterdevice described in the latter patent gazette, there is required noadjustment in timings to rotate color filters, to open/close the pixelsin the liquid crystal shutter device, and to move the photosensitivepaper, enabling to form an extremely precise image. It is also possibleto form the image by the pixels of the other line even in the spacesbetween the pixels which are required for wirings, enabling to form ahigh-quality and streak-free image.

However, when adopting the structure of the liquid crystal shutterdevice described in the latter patent gazette, there has been a problemthat the lead-out electrodes for the center pixel row, namely the pixelrow arranged as a second color, are wired by detouring around perimetersof pixel electrodes of first or third color pixels arranged at outersides, so that driving waveform for the second color pixels affectsopen/close of the first or third color pixels to thereby cause anorthogonal band-shaped image irregular with respect to the relativemoving direction of the photosensitive paper.

Hence, the configuration and the problem of the conventional liquidcrystal shutter device will be described using FIG. 28 to FIG. 30 andFIG. 7. FIG. 28 is a plan view showing a conventional liquid crystalshutter device, FIG. 29 is a plan view for illustrating wirings ofelectrodes in the liquid crystal shutter device shown in FIG. 28, FIG.30 is a sectional view taken along line 30—30 in FIG. 29, and FIG. 7 isa graph for depicting characteristics of the liquid crystal shutterdevice. Note that the pixels shown in these drawings are quite largerthan their actual sizes for convenience of illustration.

As shown in FIG. 28 to FIG. 30, this liquid crystal shutter device has atransparent first substrate 1 and a transparent second substrate 21adhered with a given gap therebetween by a sealant 33, and the gap isfilled with liquid crystal and sealed with the sealant 33 and a closingmember 34 to thereby hold the liquid crystal between the substrates 1and 21 as a liquid crystal layer 32. In the optical printer employingthis liquid crystal shutter device, as light colors to be irradiated toa photoreceptor, three colors of red (R), green (G), and blue (B) areused, and pixel rows are arranged in the liquid crystal shutter deviceto correspond to respective colors, as shown in FIG. 28. A single pixelrow at the center is denoted by G pixel row 300, and two rows of an Rpixel row 200 and a B pixel row 400 are arranged at the outer sidesthereof, the respective pixel rows being composed of a plurality ofpixels aligned in two lines as mentioned before.

Focusing on the respective pixels, as shown in FIG. 29 and FIG. 30, assignal electrodes made from a transparent conductive film, there arearranged, on the first substrate 1, the pixel electrodes for forming:the first line pixels of the R pixel row 200, such as an R1 a pixel 2,an R1 b pixel 4 which is arranged apart from the R1 a pixel 2 by onepixel size in the aligning direction, and the like; and the second linepixels of the R pixel row 200 such as an R2 a pixel 3 and the like whichare arranged apart a little from the first line pixels by misaligningwith the first line pixels by one pixel size at the same pitches. InFIG. 29, a reference number 11 representatively denotes an R1 a pixelelectrode forming the R1 a pixel 2, and only part of the pixels areshown in the drawing for convenience of illustrating.

Additionally, the R1 a pixel electrode 11 for example connects with anR1 a connecting electrode 16 via an R1 a lead-out electrode 15 tothereby connect with a first driving integrated circuit (IC) 61 via theR1 a connecting electrode 16, whereby it is possible to apply drivingsignals to the R1 a pixel electrode 11 from the first driving IC 61. Thesame is equally true of the other pixel electrodes and whereby it ispossible to apply driving signals from the first driving IC 61 to eachpixel electrode. Besides, the first driving IC 61 is connected with afirst FPC 63 via a not-shown anisotropic conductive film provided on thefirst substrate 1, and the first FPC 63 applies required signals fromoutside to the first driving IC 61.

Further, there are arranged the pixel electrodes for forming the firstline pixels of the G pixel row 300 at a position apart from the secondline of the R pixel row 200 farther than the space between the lines ofthe R pixel row 200. A G1 a pixel electrode 13 for example for forming aG1 a pixel 7 connects with a G1 a connecting electrode 17 via a G1 alead-out electrode 18 to thereby connect with the first driving IC 61via the G1 a connecting electrode 17. The same is equally true of theother pixel electrodes, and their lead-out electrodes detour around therespective pixel electrodes which form the pixels of the R pixel row 200and are led out through the spaces therebetween to the respectiveconnecting electrodes so that the other pixel electrodes connect withthe first driving IC 61 via the lead-out electrodes and the connectingelectrodes.

Furthermore, there are arranged the pixel electrodes for forming thesecond line pixels of the G pixel row 300 such as a G2 a pixel 8 and thelike. Moreover, at a position apart therefrom in the same distance as ofthe R pixel row 200 second line and the G pixel row 300 first line,there are arranged the pixel electrodes for forming the first linepixels of the B pixel row 400 such as a B1 a pixel 9 and the like, andthe second line pixels of the B pixel row 400 such as a B2 a pixel 10and the like.

These pixel electrodes are arranged substantially symmetric with respectto the pixel electrodes for forming the first and second line pixels ofthe R pixel row 200 and the first line pixels of the G pixel row 300,and connect with a second driving IC 62 provided on the counter side ofthe first driving IC 61 via the lead-out electrodes led out orthogonallyto the aligning direction of the pixel electrodes and the connectingelectrodes. Also, here, the lead-out electrodes led out from the pixelelectrodes for forming the second line pixels of the G pixel row 300provided in the center side detour around the pixel electrodes forforming the pixels of the B pixel row 400 and pass through the spacestherebetween to thereby connect with the respective connectingelectrodes. Similarly, the second driving IC 62 connects with a secondFPC 64 via a not-shown anisotropic conductive film provided on the firstsubstrate 1, so that the second FPC 64 applies required signals fromoutside to the second driving IC 62.

Meanwhile, as a common electrode made of a transparent conductive film,there is provided a counter electrode 28 on the liquid crystal layer 32side surface of the second substrate 21. Inside the sealant 33, thecounter electrode 28 is provided in a rectangular shape so as to faceall pixel electrodes for forming the pixels of respective pixel rows tothereby connect with an RGB pad electrode 47 provided outside of thesealant 33.

With such pixel electrodes and counter electrode 28, this liquid crystalshutter device achieves a high contrast ratio, in which a static drivebeing one liquid crystal driving method for increasing the responsespeed of the liquid crystal layer 32 is performed.

Also, on the counter electrode 28, there is provided a black matrix (BM)24 as a light shield film. The black matrix 24 is provided inside thesealant 33 and slightly inside the counter electrode 28 so as todirectly border on the counter electrode 28. Accordingly, when using aconductive light shield film such as a metal film and the like for theblack matrix 24, the counter electrode 28 and the black matrix 24 havethe same electric potential. In the black matrix 24, there are stillprovided BM openings 29 in portions corresponding to the respectivepixel electrodes provided on the first substrate 1, the BM opening 29being smaller than the pixel electrode in area. The overlapped portionof the pixel electrode and the BM opening 29 forms the pixel where theamount of transmitted light is practically controlled.

Still, on the opposite side surface of the liquid crystal layer 32 ofthe first substrate 1, a first polarizer 71 is provided, and on theopposite side surface of the liquid crystal layer 32 of the secondsubstrate 21, a second polarizer 73 is provided. The voltages applied tothe liquid crystal layer 32 by the respective pixel electrodes and thecounter electrode 28 are changed, and the transmitting state of lightrays 75 transmitting through the pixel portions is controlled by thefirst polarizer 71, the second polarizer 73, and the liquid crystallayer 32, so that irradiated light amount to the not-shownphotosensitive member is controlled.

In the conventional liquid crystal shutter device mentioned before, thecounter electrode 28 is formed substantially all over the inside of thesealant 33 on the second substrate 21 without regard to the arrangementof pixel rows. Hence, not only the pixel electrodes but also thelead-out electrodes inevitably face the counter electrode, and thereforewhen applying voltages to between the respective pixel electrodes andthe counter electrode 28, the voltages with the same electricalpotentials are also applied to between the lead-out electrodescorresponding to the pixel electrodes and the counter electrode 28. As aresult, driving signals to one pixel affect the voltages to be appliedto the liquid crystal layer 32 at the other pixel via the counterelectrode 28, and thus affect the transmittance of the other pixels inthe end.

As with the example described above, when the three pixel rows areprovided corresponding to the three colors of lights, the lead-outelectrodes corresponding to the pixels of the inner side pixel row(here, G pixel row 300) are led out longer, so that their areas facingthe counter electrode 28 become larger, besides, they are led outthrough near the pixel electrodes and the lead-out electrodescorresponding to the pixel rows of the outer sides (here, the R pixelrow 200 and the B pixel row 400), so that the driving signals to thepixels of the inner side pixel row strongly affect the transmittance ofthe pixels of the outer side pixel rows.

In this regard, more detailed description will be provided. In theconventional liquid crystal shutter device mentioned above, a structurecan be adopted in which, at 0th (level of) tone, a time period duringwhich voltages having a larger absolute value is applied to the liquidcrystal layer 32 is at the minimum and the transmittance is at themaximum, at 255th tone, the time period during which voltage having alarger absolute value is applied to the liquid crystal layer 32 is atthe maximum and the transmittance is at the minimum, and 127th tone isseen as a medium. In such a structure, after fixing the signals to beapplied for example to the R1 a pixel 2 to 127 tones signals, if tonesof the first line pixels of the G pixel row, of which lead-outelectrodes are led out around the R pixel row side, are shifted from 127tones states to 255 tones sequentially pixel by pixel, the transmittancegradually changes despite the voltages to be applied to the R1 a pixel 2are fixed. A curving line X in FIG. 7 shows this change.

In FIG. 7, the horizontal axis represents the number of first linepixels of the G pixel row which have been shifted from 127th tone to255th tone, and the vertical axis represents the change in thetransmittance at the focused R1 a pixel 2. As shown in the graph, ifsuch one G pixel as connected with the lead-out electrode providedbetween the R1 a pixel 2 and the R1 b pixel 4 in the first line isshifted from 127th tone to 255th tone, the transmittance in the focusedR1 a pixel 2 goes away from the target values. Similarly, if an adjacentG pixel of the same line is shifted from 127th tone to 255th tone, thetransmittance at the focused R1 a pixel 2 goes further away from thetarget values. When the number of the G pixels shifted from 127th toneto 255th tone is increased to 10, the transmittance at the focused R1 apixel 2 changes by about 3% from the initial transmittance at 127thtone. This means that the exposed amount at one pixel deviates from atarget exposure amount by the same percentages, when the photoreceptoris exposed.

When the pixels of the G pixel row connected with the lead-outelectrodes passing through the vicinity of the other pixels of the Rpixel row are shifted in tone, the transmittance of the pixels of the Rpixel row similarly deviates from the target values. These deviationsappear as a band-shaped image irregular on a printed paper. Such aproblem occurs also between the second color pixels (G pixels) and thethird color pixels (B pixels), resulting in the similar band-shapedimage irregular.

This band-shaped image irregular is specifically distinct when thepixels of respective colors are away from each other, and the imageirregular still remains when they are close to each other, even thoughit is indistinctive. Besides, when the pixels of respective colors areclosely provided, it is still difficult to separate colors, and opticalsystem becomes complicated. Specifically, when increasing light amount,a light source becomes larger, and thus it is difficult to provide themclosely.

In its essence, in the conventional liquid crystal shutter device asshown in FIG. 28 to FIG. 30, there is such a problem that the pixels ofthe two outer side rows are largely affected on their lighttransmittance when signals are applied to the center row pixels.

Should the liquid crystal shutter device of a matrix type be employedhere, the above-described influence on the image irregular can belessened, while response speed and contrast ratio also fall to therebycause printing time increase and image quality down. In addition, it isrequired to closely provide the light sources of the respective colors,so that light interference and color mixture occur. Even though thelight sources are turned on in sequence for preventing color mixture,printing time and the light amount volatility of the light sourcesincrease as compared to the case where the light sources are turned onsimultaneously for printing, since the lights are turned on for examplein the order of red, green, and blue in a time-shared manner.

It is an object of the invention to bring solutions to such a problemand make the liquid crystal shutter device provided with a plurality ofpixel rows capable of controlling light transmittance of the pixelscomposing the pixel rows to a desired value and controlling lightirradiation to the photosensitive member appropriately, so that a highquality of image without image irregular can be formed.

DISCLOSURE OF THE INVENTION

In order to attain the previously-described object, the invention ismade as a liquid crystal shutter device which includes a liquid crystalcell having a first substrate, a second substrate and liquid crystalsandwiched therebetween, pixel electrodes being signal electrodes andlead-out electrodes provided on the first substrate, counter electrodesbeing common electrodes facing the pixel electrodes, provided on thesecond substrate, and a plurality of pixel rows comprising pixels eachformed by an overlapped portion of the pixel electrode and the counterelectrode, the liquid crystal shutter device controlling lightirradiation to a photosensitive member continuously and relativelymoving in a direction orthogonal to the pixel rows, in which the counterelectrodes are separately provided for each of the pixel rows.

In such a liquid crystal shutter device, preferably, there is furtherprovided a connector for electrically connecting the counter electrodesfor each of the pixel rows, in which, preferably, the connector isprovided outside of a liquid crystal shutter function portion in whichthe pixel rows are arranged.

Further, the counter electrodes preferably include pixel counterelectrodes each corresponding to each of the pixel electrode and commonconnecting electrodes for electrically connecting the pixel counterelectrodes. Furthermore, the common connecting electrodes preferablyinclude lacing electrodes provided alongside the pixel rows and take-outelectrodes for connecting the pixel counter electrodes and the lacingelectrodes, in which preferably the pixel counter electrode is formed inan almost same shape as of the pixel electrode.

Moreover, the pixels composing the pixel rows are preferably aligned intwo lines for each pixel row at same pitches as of a pixel size is analigning direction, the pixels of one of the two lines and the pixels ofthe other line being arranged at positions misaligning with each otherby one pixel size in respective aligning directions.

In another case, the pixels composing the pixel rows are preferablyaligned in two lines for each pixel row at same pitches as of a pixelsize is an aligning direction, the pixels of one of the two lines andthe pixels of the other line being arranged at positions misaligningwith each other by one pixel size in respective aligning directions, inwhich preferably each of the counter electrodes is provided in anone-band shape for the pixel electrodes composing the pixels aligned intwo lines.

In still another case, each of the counter electrodes are preferablyprovided in a band shape for the pixel electrodes composing the pixelsaligned in two lines, separately for each line.

Also, in the above-described liquid crystal shutter device, preferably,the common connecting electrode includes a lacing electrode providedalongside the pixel rows and a take-out electrode for connecting thepixel counter electrodes and the lacing electrodes, and the lacingelectrodes are provided on both sides of the pixel counter electrodesaligned in two lines and the take-out electrodes taken out from thepixel counter electrodes aligned in two lines are connected with thelacing electrode on corresponding side, respectively.

In another case, the lacing electrodes are preferably provided on oneside of the pixel counter electrodes aligned in two lines, and thetake-out electrodes connect in common respective pair of pixel counterelectrodes composing the pixel counter electrodes aligned in two linesand also connect the pair of pixel counter electrodes with the lacingelectrodes.

Further, in these liquid crystal shutter devices, in an overlappedportion of the lead-out electrode and the lacing electrode, preferably,either of the lead-out electrode or the lacing electrode is made smallin line width as compared to the remaining portions thereof.

Alternatively, in the above-described liquid crystal shutter device,preferably, three pixel rows are provided as the plurality of pixel rowsin which, preferably, the three pixel rows correspond to respectivecolors of red (R), green (G), and blue (B), in which, preferably, inoutside two pixel rows out of the three pixel rows, the counterelectrode includes pixel counter electrodes each corresponding to eachof the pixel electrodes and common connecting electrodes forelectrically connecting the pixel counter electrodes, and in a centerpixel row, the counter electrode is formed in a band shape so as to facethe pixel electrodes of corresponding pixel row.

Moreover, in the above-described liquid crystal shutter device,preferably, there is further provided a metal-plated layer for portionsof the counter electrodes except those portions facing the pixelelectrodes.

In another case, preferably, a metallic light shield film is provided onthe second substrate with an insulating film therebetween, in which,preferably, the light shield film is provided separately for each of thepixel rows. In still another case, preferably, there is provided a lightshield film connector for electrically connecting the light shield filmsseparately provided for each of the pixel rows.

In these liquid crystal shutter devices, preferably, a pad electrode isfurther provided on the second substrate for supplying the light shieldfilms with electric signals, preferably, a connecting electrode facingthe pad electrode via the insulating film is still further provided onthe second substrate, in which, preferably, a conductive area is formedin the insulating film between the pad electrode and the connectingelectrode, and preferably, there is further provided a light shield filmdriving circuit for supplying the connecting electrode with light shieldfilm driving signal, the light shield film driving circuit supplying thepad electrode with the light shield film driving signal from theconnecting electrode via the conductive area.

Preferably, there is provided a light shield film driving circuit forsupplying the connecting electrode with light shield film drivingsignal, preferably, the light shield film driving circuit supplying thepad electrode with an AC light shield film driving signal from theconnecting electrode via the insulating film.

In these cases, preferably, the light shield film driving signal has amedium voltage of a voltage range being applied to the liquid crystal bythe pixel electrodes and the counter electrodes or a center voltage ofthe light shield film driving signal is the medium voltage.

Preferably, there is provided an external light shield member on a sideof the first substrate or the second substrate opposite to the liquidcrystal.

In the above-described liquid crystal shutter devices, the counterelectrodes are provided separately for respective pixel rows, enablingto reduce the facing areas of the counter electrodes and the lead-outelectrodes. Accordingly, it is possible to lower the effect of voltagesapplied to between the counter electrodes being common electrodes andthe lead-out electrodes. As a result, it is possible to lower such aneffect as caused by the driving signals applied to one pixel andaffecting the other pixels in view of transmittance. Additionally, forexample, when the pixel counter electrodes and the common connectingelectrodes are provided as the counter electrodes, and/or the lacingelectrodes and the take-out electrodes are provided as the commonconnecting electrodes, further effectiveness can be obtained.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view for illustrating an arrangement of electrodes andlight shield films in a liquid crystal shutter device according to afirst embodiment of the invention;

FIG. 2 is a partial plan view partially showing inside of an oval A inFIG. 1 by enlarging the same;

FIG. 3 is a partial sectional view showing part of the section takenalong line 3—3 in FIG. 2;

FIG. 4 is a schematic view for illustrating an operation of an opticalprinter provided with the liquid crystal shutter device shown in FIG. 1;

FIG. 5 is a schematic sectional view taken along line 5—5 in FIG. 4;

FIG. 6 is a view showing driving signals for driving the liquid crystalshutter device shown in FIG. 1;

FIG. 7 is a graph for depicting characteristics of the liquid crystalshutter device and a conventional liquid crystal shutter device;

FIG. 8 is a partial plan view for illustrating an arrangement ofelectrodes and light shield films in a liquid crystal shutter deviceaccording to a second embodiment of the invention;

FIG. 9 is an enlarged partial plan view showing a part of FIG. 8, inwhich a sealant and insulating films are also shown;

FIG. 10 is a view omitting to illustrate the sealant and the insulatingfilms included in FIG. 9;

FIG. 11 is a partial sectional view showing a part of the section takenalong line 11—11 in FIG. 9;

FIG. 12 is a partial plan view corresponding to FIG. 9 for illustratingan arrangement of electrodes and light shield films in a liquid crystalshutter device according to a third embodiment of the invention;

FIG. 13 is a partial sectional view showing a part of the section takenalong line 13—13 in FIG. 12;

FIG. 14 is a partial plan view corresponding to FIG. 12 showing aconfiguration of lead-out electrodes and lacing electrodes according toa modification example of the third embodiment of the invention;

FIG. 15 is a partial plan view corresponding to FIG. 12 for illustratingan arrangement of electrodes and light shield films in the liquidcrystal shutter device according to a fourth embodiment of theinvention;

FIG. 16 is a partial plan view corresponding to FIG. 8 for illustratingan arrangement of electrodes and light shield films in a liquid crystalshutter device according to a fifth embodiment of the invention;

FIG. 17 is a plan view corresponding to FIG. 1 for illustrating anarrangement of electrodes and light shield films in the liquid crystalshutter device according to a sixth embodiment of the invention;

FIG. 18 is a plan view corresponding to FIG. 1 for illustrating anarrangement of electrodes and light shield films in a modificationexample thereof;

FIG. 19 is a plan view corresponding to FIG. 1 for illustrating anarrangement of electrodes and light shield films in another modificationexample thereof;

FIG. 20 is a partial sectional view corresponding to FIG. 13 showing apart of the section of a liquid crystal shutter device according to aseventh embodiment of the invention;

FIG. 21 is a partial plan view corresponding to FIG. 9 showing aconfiguration of a liquid crystal shutter device according to a eighthembodiment of the invention;

FIG. 22 is a partial sectional view taken along a part of line 22—22 inFIG. 21;

FIG. 23 is a partial plan view corresponding to FIG. 9 showing aconfiguration of a liquid crystal shutter device according to a ninthembodiment of the invention;

FIG. 24 is a partial sectional view taken along a part of line 24—24 inFIG. 23;

FIG. 25 is a partial plan view corresponding to FIG. 8 showing aconfiguration of the liquid crystal shutter device according to thefirst embodiment of the invention where a first modification example isapplied;

FIG. 26 is a partial plan view showing a configuration of the same wherea second modification example is applied;

FIG. 27 is a partial plan view corresponding to FIG. 2 showing aconfiguration of the same where a third modification example is applied;

FIG. 28 is a plan view of a conventional liquid crystal shutter device;

FIG. 29 is a plan view for illustrating wirings of electrodes in theliquid crystal shutter device shown in FIG. 28; and

FIG. 30 is a sectional view taken along line 30—30 in FIG. 29.

BEST MODE FOR CARRYING OUT THE INVENTION

With the purpose of detailing the invention, some embodiments of theinvention will be described in conjunction with the accompanyingdrawings.

First Embodiment: FIG. 1 to FIG. 7

First, a first embodiment of a liquid crystal shutter device of theinvention and an optical printer provided with the liquid crystalshutter device will be described. FIG. 1 is a plan view for illustratingan arrangement of electrodes and light shield films in the liquidcrystal shutter device, FIG. 2 is a partial plan view partially showinginside of an oval A in FIG. 1 by enlarging the same, FIG. 3 is a partialsectional view showing a part of the section taken along line 3—3 inFIG. 2, FIG. 4 is a schematic view for illustrating an operation of theoptical printer, FIG. 5 is a schematic sectional view taken along line5—5 in FIG. 4, FIG. 6 is a diagram showing driving signals for drivingthe liquid crystal shutter device shown in FIG. 1, and FIG. 7 is a graphfor depicting characteristics of the liquid crystal shutter device. Notethat pixels shown in these drawings are quite larger than their actualsizes for convenience of illustration. In addition, for portionscorresponding to the portions shown in FIG. 28 to FIG. 30 referred to inBACKGROUND TECHNOLOGY, the same reference numbers are used in thesedrawings.

The optical printer employing the liquid crystal shutter deviceaccording to the embodiment is, as shown in FIG. 4, a device to form animage 104 to a surface of a photosensitive paper 101 being aphotosensitive member by exposing the photosensitive paper 101 whilemoving a liquid crystal shutter array 102 being an aligner provided withthe liquid crystal shutter device in a moving direction 103 relativelyto the photosensitive paper 101. At this point, the above-mentionedrelative movement may be performed by moving the photosensitive paper101 or by moving the liquid crystal shutter array 102. In a physicaloptical printer, there are provided a supporting member for supportingthe liquid crystal shutter array 102 and a mechanism for performing therelative movement, yet, illustrations thereof are omitted here.

In the liquid crystal shutter array 102, as shown in FIG. 5, respectivelight source substrates for R, G, B are mounted on upper inside portionsof an outer housing 125 such that their mounted positions areadjustable, respectively. Of these an R substrate 107 being a firstmounting substrate is mounted on one side surface, a G substrate 113being a second mounting substrate is mounted on an upper undersurface,and a B substrate 117 being a third mounting substrate is mounted on theother side surface, respectively.

On the R substrate 107, there are fixed a plurality of first lightemitter aligned in an orthogonal direction to the moving direction 103of the liquid crystal shutter array 102, each of which comprises of an Rlight emitting element 108 being an LED, an R scattering member 109, andan R lens member 110. On the G substrate 113, there is fixed a secondlight emitter comprising a white light lamp for G 114 for emitting whitelight, a G lens member 115, and a G color filter 116, which is formedlengthwise in the orthogonal direction to the moving direction 103. And,on the B substrate 117, there is fixed a third light emitter comprisinga white light lamp for B 118 for emitting white light, a B lens member119, and a B color filter 120, formed lengthwise in the orthogonaldirection to the moving direction 103. These first, second, and thirdlight emitter compose a light source of the liquid crystal shutter array102.

Further, in front of the R lens member 110, there is disposed an Rreflecting member 111 for reflecting an R light ray 112 being a firstcolor light emitted by the first light emitter toward the photosensitivepaper 101, in front of the B lens member 119, there is disposed a Breflecting member 121 for reflecting a B light ray 124 being a thirdcolor light emitted by the third light emitter toward the samephotosensitive paper 101, and a G light ray 123 being a second colorlight emitted by the second light emitter is condensed to an adequateirradiation spot by the G lens member 115.

Meanwhile, in the lower inside portion of the outer housing 125, thereare mounted a liquid crystal shutter 105 being an optical shutter forcontrolling light transmittance by electric signals, and a lens array106 for condensing the light passed through the liquid crystal shutter105 so that the light is focused on the photosensitive paper 101.

While moving a top surface of the photosensitive paper 101 relatively tosuch a liquid crystal shutter array 102 as described above, therespective light emitter emit lights to expose the photosensitive paper101 while controlling irradiation of respective color lights irradiatedfrom the light emitter by adequately transmitting or shielding them bythe liquid crystal shutter 105, so that the image 104 can be printed outon the top surface of the photosensitive paper 101.

The liquid crystal shutter 105 used in such an optical printer is theliquid crystal shutter device of the invention. Its generalconfiguration and arrangement of pixels are the same as those describedin BACKGROUND TECHNOLOGY using FIG. 28, that is, there are provided atransparent first substrate 1 and a transparent second substrate 21adhered by a sealant 33 with a given gap therebetween, and a liquidcrystal layer 32 filling the gap and sandwiched between the substrates.It is notable that the sealant 33 is omitted to illustrate in FIG. 1 toFIG. 7 used for the description of the first embodiment, whereas, it isalso provided here as in the conventional device shown in FIG. 28 andFIG. 29.

Further, there are provided three pixel rows of an R pixel row 200, a Gpixel row 300, and a B pixel row 400 corresponding to the three colorsof lights to be irradiated. The pixels composing the respective pixelrows are aligned in two lines at the same pitches as of the pixel sizein the aligning direction thereof, and those pixels of one of the twolines and those pixels of the other line are arranged at positionsmisaligning with each other by one pixel size in respective aligningdirections.

Such a pixel arrangement enables to lead out the lead-out electrodes ofthe pixels of different lines or different pixel rows through spacesbetween the pixels of respective lines. Moreover, when spaces betweenthe pixel rows are made larger than a space between the lines of onepixel row, light separation in the case where different colors of lightsare irradiated to each pixel row is facilitated.

Also, the arrangement of pixel electrodes being signal electrodes andlead-out electrodes which are provided on the first substrate 1, and thearrangement of connecting electrodes and respective driving ICs 61, 62are similar to those described in BACKGROUND TECHNOLOGY using FIG. 28 toFIG. 30. That is a structure in which the pixel electrodes to formpixels are arranged at such positions on the first substrate 1 ascorresponding to the pixels of respective lines of respective pixelrows, the lead-out electrodes are led out from the pixel electrodes tothe connecting electrodes connected with the driving ICs, and respectivepixel electrodes are connected with a first driving IC 61 or a seconddriving IC 62 via the lead-out electrodes and the connecting electrodes,so that the respective driving ICs 61, 62 can apply driving signals torespective pixel electrodes.

However, in this liquid crystal shutter device, the arrangement of thelight shield films and the counter electrodes are as shown in FIG. 1 toFIG. 3. Note that, in FIG. 1 and FIG. 2, the light shield films andtheir connecting electrodes are shown by dashed and dotted lines, andthe sealant, polarizers, and a retardation film are omitted toillustrate, for convenience of viewing. Further, in the overlappedportions of the lead-out electrodes and the counter electrodes, theunderlying counter electrodes are shown by broken lines with a view todistinguish their vertical positions. The same is equally true of theplan views used in the descriptions below unless otherwise noted. Inaddition, in FIG. 1, the pixel electrodes, the pixel counter electrodesand the like shown are only part thereof which are arranged at endportions, omitting the rest of them in the drawing.

In this liquid crystal shutter device, on the second substrate 21, asconductive light shield films, there are provided an R black matrix 25,a G black matrix 26, and a B black matrix 27, which are made of achromium film being a metal film, corresponding to respective colors ofthe pixel rows. Specifically, in a liquid crystal shutter functionportion in which black matrix (BM) gaps 31 are provided between theblack matrixes corresponding to the respective pixel rows, the pixelrows are provided, and wiring electrodes are led out, the black matrixis provided in three lines separately for each of the R, G, and B pixelrows. The respective black matrixes 25, 26, 27 are provided with BMopenings 29 being smaller than the pixel electrodes at such positions ascorresponding to the respective pixel electrodes provided on the firstsubstrate 1, and the overlapped portions of the pixel electrodes and theBM openings 29 form the pixels where transmitted light amount ispractically controlled.

Further, outside of the liquid crystal shutter function portion on aleft side of FIG. 1, there are provided BM coupling portions 49 beinglight shield film connector to thereby electrically connect therespective black matrixes 25, 26, 27, and in a portion of the secondsubstrate 21 projecting from the first substrate 1 outside the sealant33, there is provided a BM pad electrode 50 so that electric signals canbe applied to the respective black matrixes 25, 26, 27 therefrom.Incidentally, even though the respective black matrixes 25, 26, 27, theBM coupling portions 49, and the BM pad electrode 50 are differentlynamed, these can be made of a same material, and provided in a sameprocess by patterning and so forth.

Note that the black matrix gap 31 is shown smaller than the blackmatrixes in width in the drawing because the pixels are shown largerthan their actual sizes, however, a practical pixel has a extremelysmall size in proportion to the substrate, and thus the pixel row isalso small in width, where the black matrix is allowed to have a smallwidth to the extent that the condensed light to the pixel row can notdetour therearound, so that it is possible to reduce the area of theblack matrix and instead to provide wider gap for the black matrix gap31.

Although such a black matrix is not necessarily made of a conductivematerial, it is preferable to use a metal film such as a chromium filmand the like rather than an insulating material such as resin or thelike, since the former exhibits higher light shielding effect eventhough it is a thin film. Accordingly, it is inevitably required in thiscase to use the conductive material.

Further, substantially all over the inside of the sealant 33 on thesecond substrate 21 including on the respective black matrixes 25, 26,27, there are provided an insulating film 30 made of photosensitiveacrylic resin, and on the insulating film 30, the counter electrodesmade of a transparent conductive film are provided as common electrodes.Incidentally, the insulating film 30 is provided only inside of thesealant 33 for the reason that the insulating film 30 is weaker than atransparent conductive film or the like in view of mechanical strength,hence, when the insulating film 30 is provided in such a position asoverlaps the sealant 33, adhesiveness between the sealant 33 and thesecond substrate 21 cannot be ensured. In addition, in this approach,the BM pad electrode 50 does not have any thick insulating film 30thereon, eliminating the need of removing the insulating film thereon.

This liquid crystal shutter device is structured to have, as the counterelectrodes, for outside two rows of the R pixel row 200 and the B pixelrow 400, pixel counter electrodes provided in a manner corresponding torespective pixel electrodes, formed at positions facing respective pixelelectrodes, and having substantially the same shape as of the pixelelectrodes; and common connecting electrodes for electrically connectingthe respective pixel counter electrodes, the common connectingelectrodes having lacing electrodes provided alongside the pixel rowsand take-out electrodes for connecting the respective pixel counterelectrodes and the lacing electrodes.

Specifically, in the case for example of an R1 a pixel 2, as shown inFIG. 2, an R1 a pixel counter electrode 35 is provided at a positionfacing an R1 a pixel electrode 11 and is connected with an R1 lacingelectrode 37 via an R1 a take-out electrode 36. The overlapped portionof the R1 a pixel electrode 11 and the R1 a pixel counter electrode 35forms the pixel. Among the overlapped portion, however, that functionsactually as pixel is only a part thereof that overlapping the BM opening29, as previously mentioned.

As for the rest of the pixel electrodes composing the first line pixelsof the R pixel row 200, similarly, there are provided the counterelectrodes which are connected with the R1 lacing electrode 37 via thetake-out electrodes. Also, at the positions facing the pixel electrodescomposing the second line pixels of the R pixel row 200 such as an R2 apixel 3, there are provided the pixel counter electrodes which areconnected with an R2 lacing electrode 40 via the take-out electrodes.Altogether, the pixel counter electrodes and the pixel electrodes arealigned in a similar manner.

Here, in the liquid crystal shutter function portion, the R1 lacingelectrode 37 and the R2 lacing electrode 40 are band-shaped electrodesindependent from each other, provided at both sides of the pixel counterelectrodes aligned in two lines as in the case of the pixel electrodes,and arranged in parallel with the R pixel row 200. The take-outelectrodes from the pixel counter electrodes are connected with thelacing electrode of the corresponding side, respectively.

A similar structure is applied to those lacing electrodes provided forthe pixels of the B pixel row 400, and the pixel counter electrodeswhich are provided at the positions facing the pixel electrodescomposing the first and second line pixels are connected via thetake-out electrodes with band-shaped B1 lacing electrode 43 and B2lacing electrode 44, respectively.

Meanwhile, for the G pixel row 300 at the center, the counter electrodeis formed in a band-shape facing the pixel electrodes. Specifically, aband-shape counter electrode is provided as a G1 lacing electrode 41 soas to face all pixel electrodes composing the first line pixels of the Gpixel row 300, which, therefore, functions as the pixel counterelectrodes as well as the lacing electrode in the case of the R pixelrow 200 and the B pixel row 400. Accordingly, there is provided noelectrodes corresponding to take-out electrode. Similarly, in the secondline, there is provided a G2 lacing electrode 42. In this G pixel row300, a portion in which one pixel electrode faces corresponding lacingelectrode forms the pixel.

As mentioned above, in the liquid crystal shutter function portion,there are provided a total of six mutually independent lacingelectrodes, two for each row of the three pixel rows.

Outside the liquid crystal shutter function unit on the left side ofFIG. 1, there is provided an RGB coupling electrode 46 being a connectorfor electrically connecting these six lacing electrodes 37, 40, 41, 42,43 and 44, and in a portion where the second substrate 21 projects fromthe first substrate 1 outside the sealant 33, there is provided an RGBpad electrode 47 so that electronic signals can be applied to therespective lacing electrodes therefrom. Incidentally, the counterelectrodes including each lacing electrode and pixel counter electrode,the RGB coupling electrode 46, and the RGB pad electrode 47 can be madeof the same material and provided in the same process of patterning orso forth, even though they are differently named.

In this liquid crystal shutter device, as previously mentioned, thecounter electrodes and the black matrixes are provided with theinsulating film 30 therebetween. Therefore, the respective electrodescomposing the counter electrodes and the black matrixes are electricallyinsulated from each other by the insulating film 30, so that the counterelectrodes and the black matrixes form a capacitor with the insulatingfilm 30 therebetween.

In addition, the BM pad electrode 50 and the RGB pad electrode 47connect with a third FPC 65 to thereby connect via the third FPC 65 withan outside light shield film driving circuit which generates lightshield film driving signals to be applied to the black matrixes.Moreover, the light shield film driving circuit can be provided on thesecond substrate 21 so that the circuit connects with the BM padelectrode 50 without using FPC.

Further, in this liquid crystal shutter device, as shown in FIG. 3,there are provided a retardation film 72 and a first polarizer 71 on theopposite side surface of the liquid crystal layer 32 side of the firstsubstrate 1, and a second polarizer 73 on the opposite side surface ofthe liquid crystal layer 32 side of the second substrate 21. Thus, thevoltages applied to the liquid crystal layer 32 are changed by therespective pixel electrodes and the counter electrodes to therebycontrol the transmitting state of the light rays 75 through the pixelportions by the first polarizing plate 71, the retardation film 72, thesecond polarizing plate 73, and the liquid crystal layer 32, so that theirradiated light amount to the photosensitive paper 101 is controlled.

In this liquid crystal shutter device, the above-mentioned structure ofthe counter electrodes allow to reduce the areas of the counterelectrodes to thereby further reduce the areas of the facing portions ofthe lead-out electrodes and the counter electrodes extremely.Accordingly, it is possible to lower such an influence of those signalsapplied to the pixel electrodes via the lead-out electrodes that affectthe transmittance of the other pixels via the counter electrodes. Inparticular, it is possible to lower the influence on the first and thirdcolor pixels on both the sides, which is caused by driving waveformsapplied to the pixel electrodes for the second color row at the center.On top of that, even if voltage changes at the lead-out electrodesaffect a little the counter electrodes, the influence on thetransmittance of the pixels ends in slight, since the capacitor formedby the counter electrode and the black matrix is capable ofcounteracting the influence.

Further, the black matrixes are capacitively coupled with the lead-outelectrodes via the liquid crystal layer 32 and the insulating film 30.Meanwhile, the counter electrodes are capacitively coupled with theblack matrix via the insulating film 30. Therefore, it is possible togreatly lower an influence on the counter electrode caused by voltagechanges at the lead-out electrodes via the black matrixes heldtherebetween.

Furthermore, between the liquid crystal shutter function portion and thesealant 33, the respective RGB black matrixes are connected with eachother via the BM coupling portion 49, and also the respective lacingelectrodes are connected with each other via the RGB coupling electrode46, whereby it is allowed to connect them with outside circuits onlywith one BM pad electrode 50 and one RGB pad electrode 47, respectively.Accordingly, the number of the pad electrodes can be reduced, wherebypossible to reduce the projecting areas of the second substrate 21 fromthe first substrate 1 and to increase the areas of the pad electrodes,so that the connection is stabilized. Also, it is easily possible toestablish connection with the not-shown outside circuits by removing theinsulating films 30 on the respective pad electrodes in view ofadvantages such as small number of pat electrodes, larger connectionareas, concentrated removal areas of the insulating film 30, andconnection at low resistance.

As driving signals for driving the liquid crystal shutter device of theabove-mentioned structure, those for example shown in FIG. 6 can beused. In FIG. 6, the horizontal axis indicates time and the verticalaxis indicates voltages. The reference signs T1, T2, T3 on thehorizontal axis are flame periods for exposing one position,respectively. The flame periods are divided into a liquid crystalrefresh period Tr1 for refreshing transmittances of pixels once to acertain value, and a first half selection period Ts1 and a latter halfselection period Ts2 for controlling the transmittances of the pixels bythe signals corresponding to the image to be formed.

The reference numeral 127 denotes a counter electrode driving signal tobe applied to a counter electrode, the reference numeral 128 denotes apixel electrode driving signal to be applied to a pixel electrode, andthe reference numeral 129 denotes a combined signal to be applied to theliquid crystal layer 32 which equals to the difference between thecounter electrode driving signal 127 and the pixel electrode drivingsignal 128. The reference numerals 130 and 131 denote a first BM drivingsignal and second BM driving signal respectively, they are light shieldfilm driving signals to be applied to the black matrixes.

In this liquid crystal shutter device, so-called normally white mode isadopted, where the transmittance becomes large (white) when the voltagesapplied to the liquid crystal layer 32 is 0 (zero), and thetransmittance becomes small (black) when the voltages applied have alarge absolute value. In the liquid crystal refresh period Tr1, voltagesof V5–V1 and V1–V5 are alternately applied to the liquid crystal layer32 alternately by the counter electrode driving signal 127 and the pixelelectrode driving signal 128 to thereby bring all pixels into blackstates. This is because the higher transmittance can be obtained bymaking them once in black states before making them in white states.

In the selection period Ts1 thereafter, a voltage of V5 is applied tothe counter electrodes, and a voltage of V1 or V5 is applied to thepixel electrodes while changing the ratio of application time inaccordance with the tones, in other words, where a pulse widthmodulation driving is performed. As in T1, when a voltage of V1 isapplied consistently, transmittance at the pixel is minimized, when avoltage of V5 is applied consistently as in T3, the transmittance ismaximized, and when both the voltages are applied as in T2, the pixeltransmittance results in a gray tone. In the latter half selectionperiod Ts2, a signal which is symmetrical to the signals applied in theperiod Ts1 with respect to a voltage of V3 is applied during the sametime period to thereby prevent the liquid crystal layer 32 fromreceiving DC voltages.

Meantime, in this liquid crystal shutter device, the black matrixes arealso conductive, it is whereby conceivable that the voltage changes atthose lead-out electrodes facing the black matrixes affect the voltagesof the other electrodes via the black matrixes, so that thetransmittances of the pixels are changed. The black matrixes are distantfrom the lead-out electrodes and the insulating film 30 with a lowrelative dielectric constant exists between the black matrix andlead-out electrodes, proving that the effect is not so large. However,the black matrixes need enough width to prevent light detouringtherearound, meaning it is impossible to reduce its arrangement areas somuch as compared to the counter electrodes, so that it is contrived tolower the influence by fixing potentials of the black matrixes to apredetermined level.

The signals for this purpose are first BM driving signals 130 and secondBM driving signals 131. With application of these signals, the blackmatrixes are kept at 0V, which is the intermediate potential of thedriving signals of the liquid crystal cell, to thereby prevent thevoltage changes at the lead-out electrodes from affecting the otherelectrodes via the black matrixes. Incidentally, the first BM drivingsignals 130 are those signals used when the light shield film drivingcircuit or the FPCs, and the black matrixes are connected with eachother at low resistance at the BM pad electrode 50, and the second BMdriving signals 131 are those signals used when capacitively coupled viaa thin insulating film. In the latter case, when rectangular waves at avoltage of V5–V1 and V1–V5, mainly at 0V being the intermediatepotential, are applied as AC driving signals, then stabilized at 0V withtime due to the capacitive coupling. These BM driving signals 130 and131 can be generated by a simple circuit composed of a reference voltagegenerating circuit, a reference clock generating circuit, a frequencydividing circuit, and so forth.

Incidentally, although the voltages applied by the BM driving signalsare not limited to the intermediate voltages, in the case of thevoltages deviated from the intermediate, effectiveness falls when thevoltages applied to the liquid crystal layer 32 is shifted to theopposite side. Therefore, the intermediate voltages are preferable.

In such a liquid crystal shutter device, in the same manner as in thecase described in BACKGROUND TECHNOLOGY using FIG. 7, after fixing thesignals to be applied to the R1 a pixel 2 to a signal of 127th tone,when the tones of all the first line pixels of the G pixel row 300 ofwhich lead-out electrodes are led out around the R pixel row 200 sideare shifted from 127th tone to 255th tone sequentially pixel by pixel,the changes in transmittance at the R1 a pixel 2 are shown in the graphin FIG. 7 by the curved line Y.

Even in this liquid crystal shutter device, some changes in thetransmittance still arise, yet, even after shifted 10 pixels of the Gpixel row 300, the transmittance changes are no more than 0.5%, provingsignificant reduction in transmittance changes as compared to theconventional device shown by the curbed line X.

Therefore, according to this liquid crystal shutter device, it ispossible to control the light transmittances at the pixels composing therespective pixel rows to desired values. And the optical printerstructured employing this liquid crystal shutter device is capable offorming a high quality of image without irregular by controlling lightirradiation to the photosensitive member in an adequate manner.

Incidentally, in this liquid crystal shutter device, the pixel counterelectrodes and the lacing electrodes are connected via the take-outelectrodes, and the positions of the lacing electrodes are providedsubstantially parallel to the pixel rows at a position different fromthe pixels to the moving direction of the photosensitive paper, wherebythe pixel counter electrodes, the take-out electrodes, or the lacingelectrodes do not face, near the pixel, the lead-out electrodescorresponding to the pixels of the different pixel row, allowing toprevent the influence of applied voltages which occurs between thepixels of the different pixel rows. Further, the lacing electrodes areprovided for each pixel line of the respective pixel rows, so that it ispossible to prevent the influence of the applied voltages from occurringvia the lacing electrodes of the different pixel rows. Furthermore, thesix lacing electrodes are provided respectively for each line ofrespective pixel rows, so that it is still possible to lower theinfluence within the same pixel row. Specifically, there occurs no imageirregular for each line, so that the reduction in irregulars in thelateral direction, which occur depending on the image, can be realizedto a large degree.

Preferably, here, for reducing the areas facing the lead-out electrodesprovided on the first substrate 1, the lacing electrodes are provided insuch a position as facing smaller number of lead-out electrodes as muchas possible. For the case for example of the R2 lacing electrode 40shown in FIG. 1, preferably, it is provided between the R pixel row 200and the G pixel row 300. In doing so, the lacing electrode does not faceany lead-out electrode led out from the pixels of the corresponding lineor the pixels of the other line of the same color row, so that thepotential changes of the lacing electrode are enabled to be lessaffected by potentials of the lead-out electrodes.

Referring to the structure of the counter electrodes, here, there is nolead-out electrode crossing over the G pixel row 300 at the center, sothat the counter electrodes corresponding to the G pixel row 300 areformed in the band-shape, however, it may be formed using the pixelcounter electrodes and the common connecting electrodes as in the caseof the R pixel row 200 and B pixel row 400.

Also, as a connection structure between the BM pad electrode 50, thethird FPC 65, and the like, such a connection structure may be adoptedas will be described in the following description of a secondembodiment.

Second Embodiment: FIG. 8 to FIG. 11

Next, a second embodiment of the liquid crystal shutter device of theinvention will be described. FIG. 8 is a partial plan view forillustrating an arrangement of electrodes and light shield films in thisliquid crystal shutter device, FIG. 9 is an enlarged partial plan viewshowing a part of FIG. 8, in which a sealant and an insulating film arealso shown, FIG. 10 is a view omitting to illustrate the sealant and theinsulating film included in FIG. 9, and FIG. 11 is a partial sectionalview showing a part of the section taken along line 11—11 in FIG. 9.Note that FPCs to be connected with the liquid crystal shutter device isomitted to illustrate in FIG. 8. In addition, in these drawings, forportions corresponding to the structure described in the firstembodiment, the same reference numerals are used.

Additionally, this liquid crystal shutter device differs from the liquidcrystal shutter device of the first embodiment in regard only to thestructure of the counter electrodes, a thin insulating film 23 providedon the insulating film 30, and a first BM connecting electrode 58 and asecond BM connecting electrode 59 provided on the BM pad electrode 50,so that the description will be provided only in this regard.

Have it beginning with the counter electrodes, this liquid crystalshutter device is structured to have the same band-shaped two lacingelectrodes for the central G pixel row 300, namely a G1 lacing electrode41 and a G2 lacing electrode 42, as in the case of the first embodiment.However, for the outside two rows, namely an R pixel row 200 and a Bpixel row 400, for each row, it has pixel counter electrodes aligned intwo lines so as to face respective pixel electrodes, a lacing electrodeon one side thereof, and take-out electrodes for commonly connectingpairs of the pixel counter electrodes composing two lines of the pixelcounter electrodes to thereby connect with the lacing electrode.

Specifically, for example as shown in FIG. 9, there are provided, in theR pixel row 200, an R1 a pixel counter electrode 35 facing an R1 a pixelelectrode 11 forming an R1 a pixel 2 and an R2 a pixel counter electrode38 facing an R2 a pixel electrode 12 forming an R2 a pixel 3 in whichthese are commonly connected, as a pair, via an R1 a R2 a inter-pixelelectrode 52 being a part of the take-out electrode to thereby connectwith an R lacing electrode 51 via an R2 a take-out electrode 39.Similarly, for the other pixel electrodes composing the pixels of the Rpixel row, there are provided the pixel counter electrodes as well, andpairs of the pixel counter electrodes of the first and second lines arecommonly connected via the take-out electrodes to thereby connect withthe R lacing electrode 51.

The same is equally true for those provided for the pixels of the Bpixel row 400, the respective pixel counter electrodes are connectedwith a band-shaped lacing electrode 83 via the take-out electrodes,respectively.

In this manner, in the liquid crystal shutter function unit, a total offour mutually independent lacing electrodes are provided, one for eachof the R pixel row 200 and the B pixel row 400, and two for G pixel row300.

Outside the liquid crystal shutter function portion on the left side ofFIG. 1, there are provided an RGB coupling electrode 46 being aconnector to electrically connect these four lacing electrodes 51, 41,42 and 83, and an RGB pad electrode 47 as in the case of the firstembodiment, so that electric signals can be applied to each of thelacing electrodes therefrom.

In this liquid crystal shutter device, as mentioned before, the lacingelectrodes for the R pixel row 200 and the B pixel row 400 are reducedto one for each row in number, allowing to reduce the areas of thelacing electrodes facing the lead-out electrodes led out from the pixelelectrodes of the G pixel row 300 as compared to the first embodimenthaving two for each row. Accordingly, the influence of driving signalsto the G pixel row 300 on transmittances of the pixels of the R pixelrow 200 and the B pixel row 400 can further be lowered as compared tothe first embodiment.

Further, in this liquid crystal shutter device, an organic film made ofacrylic resin is used for the insulating film 30, therefore, it is notpreferable for patterning to provide counter electrodes, being a commonelectrode, of a transparent conductive film directly on the organic filmdue to its weak adhesiveness. Therefore, a silicon oxide film (SiO₂)having a thickness of 100 Å to 200 Å is further provided as the thininsulating film 23 on the insulating film 30 formed of the organic film,and the counter electrodes are provided thereon. This allowsimprovements in adhesiveness and patterning accuracy of the transparentconductive film.

Incidentally, although the insulating film 30 is provided inside of asealant 33 and not on the BM pad electrode 50, the thin insulating film23 is provided all over a second substrate 21 and still on the BM padelectrode 50 as well. This is because the thin insulating film 23 doesnot exert bad effect on adhesiveness of the sealant 33, so that it canbe provided even in an overlapping portion with the sealant 33.

Similarly, when using a chromium film for the black matrix as in thecase of this liquid crystal shutter device, there is formed anonconductive natural oxide film on the chromium film, so that it isdifficult to simply ensure electrical conductivity with the circuitssuch as the FPCs at the BM pad electrode 50.

For ensuring the electrical conductivity, in this liquid crystal shutterdevice, there are provided a first BM connecting electrode 58 and asecond BM connecting electrode 59 on the thin insulating film 23provided on the BM pad electrode 50. These electrodes can be formed ofthe same material and in the same process as of the counter electrodes.Incidentally, a given gap is provided between the first BM connectingelectrode 58 and the second BM connecting electrode 59 so that theseelectrodes are insulated from each other as long as the thin insulatingfilm 23 retains its electrical insulation performance.

However, with pulse voltages or a DC voltage at around 20 volts (V)being applied to between the first BM connecting electrode 58 and thesecond BM connecting electrode 59 for a short time period, it ispossible to electrically break down the thin insulating film 23 betweenthe first BM connecting electrode 58 and BM pad electrode 50 or the samebetween the second BM connecting electrode 59 and the BM pad electrode50, so that electrical conductive portion 70 can be formed with ease, asa conductive area. In FIG. 11, there is shown a state where part of thethin insulating film 23 between the BM pad electrode 50 and the secondBM connecting electrode 59 is electrically broken down and removed, andthe electrical conductive portion 70 is formed.

As shown in FIG. 11, with a metal electrode 86 provided on an FPC basefilm 85 and an anisotropic conductive film being a mixture of polyimideresin 81 and conductive particles 82, the first and second BM connectingelectrodes 58 and 59, and the third FPC 65 are electrically connectedvia the metal electrode 86 on the third FPC 65 and the conductiveparticles 82 by heat and pressure, and the state under pressure isfirmly maintained by the polyimide resin 81. Further on the metalelectrode 86 of the third FPC 65, there is provided an FPC cover film 87for preventing erosion of the metal electrodes and electrical shortbetween the metal electrodes caused by a foreign particle.

As mentioned before, provision of the electrical conductive portion 70,and its connection with the third FPC 65 via the first and second BMconnecting electrode 58 and 59 allow assured connection at lowresistance. Furthermore, in the electrical conductive portion 70, insuch cases where voltages are applied to the black matrixes, wherecharges travel between the black matrixes and, the pixel electrodes, thelead-out electrodes, or the pixel counter electrodes arise, and thelike, there occurs stationary charge transfer in which current flows. Asa result, electrical processing is steadily performed at the electricalconductive portion 70. Accordingly, even when using chrome for the blackmatrixes and thereby generating the natural oxide film in the electricalconductive portion 70, the insulation can be broken down instantly bythe electrical processing so that conductive state can be maintained ina stable manner. This enables to enhance reliability of the device.

Incidentally, it is also possible to apply AC driving signals to theblack matrixes via capacitance formed by the BM connecting electrodes58, 59, the BM pad electrode 50, and the thin insulating film 23therebetween, without providing the electrical conductive portion 70.Further, it is still possible to provide a light shield film drivingcircuit on the second substrate 21 and connect it with the BM padelectrode 50 without using FPCs.

Third Embodiment and its Modification Example: FIG. 12 to FIG. 14

Subsequently, a third embodiment of the liquid crystal shutter device ofthe invention and its modification example will be described. FIG. 12 isa partial plan view corresponding to FIG. 9 for illustrating anarrangement of electrodes and light shield films of the liquid crystalshutter device, FIG. 13 is a partial sectional view showing a part ofthe section taken along line 13—13 in FIG. 12, and FIG. 14 is a partialplan view corresponding to FIG. 12 showing a structure of lead-outelectrodes and lacing electrodes in the modification example. In thesedrawings, for portions corresponding to the first and the secondembodiments, the same reference numerals are used.

Additionally, these liquid crystal shutter devices differ from that ofthe second embodiment in regard only to a slit-like insulating filmspace 79 provided on an insulating film 30, an inter-color sealant 66provided in the space, and the shapes of the lacing electrodes or thelead-out electrodes, so that the description will be provided only inthis regard.

Similarly, in the liquid crystal shutter device according to thisembodiment, the insulating film 30 is provided substantially all overthe inside of a sealant 33 on a second substrate 21 including on blackmatrixes. Meanwhile, as shown in FIG. 12, on a part of black matrixspace 31, there is provided the slit-like insulating film space 79having no insulating film 30. In the slit-like insulating film space 79,as shown in FIG. 13, there is provided the inter-color sealant 66 foradhering the first substrate 1 and the second substrate 21 to each otherby holding a given gap therebetween.

This inter-color sealant 66 is a mixture of epoxy resin and a spacermade of glass fiber, glass bead, or plastic bead, and adheres the firstsubstrate 1 and the second substrate 21 to each other as with thesealant 33. As was described in the first embodiment, the adhesivenessof the sealant goes low in those portions having the insulating film 30,however, this inter-color sealant 66 is provided in the slit-likeinsulating film space 79 having no insulating film 30, so that theinter-color sealant 66 is capable of surely adhering to the firstsubstrate 1 and the second substrate 21.

Incidentally, there is provided no spacer in the remaining portionsother than the sealant 33 and the inter-color sealant 66, particularlyin the pixels. This is because the spacer in the pixel affects thetransmittance control by voltage application to a liquid crystal layer32.

Still, in this liquid crystal shutter device, counter electrodes arestructured in the same manner as in the second embodiment, and there areprovided, for the G pixel row 300, the two band-shaped lacing electrodeswhich function also as pixel counter electrodes, and for the R pixel row200 and the B pixel row 400, pairs of the counter pixel electrodes whichare commonly connected via take-out electrodes respectively and arethereby connected with the lacing electrodes provided on one sidethereof.

However, those portions of respective lacing electrodes facing thelead-out electrodes are made narrower than the remaining portions inline width.

Specifically, as shown for example in FIG. 12, those portions of Rlacing electrode 51 facing the lead-out electrodes led out from pixelelectrodes of the G pixel row 300 are formed as small width portions 54having a small line width, and the remaining portions are formed as widewidth portions 53 having a wide line width. The same is equally true ofthe lacing electrodes of the B pixel row 400 even though they areomitted in the drawings. Also, for G1 lacing electrode 41 and G2 lacingelectrode 42, those portions in which the lead-out electrodes are ledout from the pixel electrodes are formed as small width portions 68 andthe remaining portions are formed as wide width portions 67.

As mentioned above, the lacing electrodes are formed to have smallerwidth for those portions facing the lead-out electrodes to therebyreduce the facing areas of the lead-out electrodes and the lacingelectrodes, so that the effect of the voltage changes at the lead-outelectrodes on the transmittance of the other pixels can be reduced. Atthe same time, the remaining portions of the lacing electrodes notfacing the lead-out electrodes are formed to have wide width, so thatresistance of the lacing electrode can be prevented from increasing.Incidentally, the lacing electrode of the G pixel row is also providedwith the wide width portions 67 in consideration of the balance with theR lacing electrode 51 and a B lacing electrode, whereas, it may beformed only with the small width portion 68 from first to last.

Note that, although an example of the lacing electrode provided with thewide width portions and the small width portions has been describedhere, the lead-out electrode may be provided with small width portions92 at portions thereof facing the lacing electrodes by making theportions narrower than the remaining portions, while the lacingelectrode having the same line width from first to last, as shown inFIG. 14. Also, in this case, it is possible to reduce the facing areasof the lead-out electrodes and the lacing electrodes, and wherebyallowed to lower the effect of the voltage changes at the lead-outelectrodes on the transmittance of the other pixels.

Fourth Embodiment: FIG. 15

Subsequently, a fourth embodiment of the liquid crystal shutter deviceof the invention will be described. FIG. 15 is a partial plan viewcorresponding to FIG. 12 for illustrating an arrangement of electrodesand light shield films in the liquid crystal shutter device. In thedrawing, for portions corresponding to the first to third embodiments,the same reference numerals are used.

Additionally, this liquid crystal shutter device differs from that ofthe third embodiment in regard only to an outline edge sealant 93provided in the vicinity of a sealant 33 and small width portionsprovided in both lacing electrodes and lead-out electrodes, so that thedescription will be provided only in this regard.

In this liquid crystal shutter device, there is provided a outline edgesealant 93 at a portion inside the sealant 33 outside the regionprovided with the insulating film 30. Although no spacers are mixed intothe sealant 33 for the purpose of adhering a first substrate 1 to asecond substrate 21 and of preventing a contaminant for example moisturefrom interfusing with a liquid crystal layer 32, the outline edgesealant 93 has a large amount of spacer interfused therewith, since theoutline edge sealant 93 is provided for stabilizing the thickness of theliquid crystal layer 32, as with an inter-color sealant 66, to therebymaintain a state of no irregular in the liquid crystal shutter functionportion of the liquid crystal layer 32.

Alternatively, the sealant 33 may be made of a material having largethermal contraction tendency, high adhesiveness, and less osmosis ofwater, as with epoxy resin, and the inter-color sealant 66 and theoutline edge sealant 93 may be made of a material having elasticity andless stress, as with acrylic resin. Otherwise, it is also possible toreduce occurrence of electrical shorts between a lot of wirings in theliquid crystal shutter function portion or between black matrixes andwirings, by interfusing conductive particles with the sealant 33 andelectrically connecting counter electrodes and the black matrixesprovided on the second substrate 21 and electrodes provided on the firstsubstrate 1 to thereby cause reallocation, and by using a spacer made ofan insulator for the inter-color sealant 66 and the outline edge sealant93.

The structure of the lacing electrodes and the lead-out electrodes isessentially the same as described in the third embodiment using FIG. 12,provided that both of the lacing electrodes and the lead-out electrodesare made smaller in width in the facing portions of the lacingelectrodes and the lead-out electrodes than the remaining portions.Specifically, as shown in FIG. 15, the lacing electrode is provided withsmall width portions 54, and the lead-out electrode is also providedwith small width portions 92.

This makes it possible to reduce the facing areas of the lacingelectrodes and the lead-out electrodes more than those in the thirdembodiment so that it is possible to lower influence of the voltagechanges at the lead-out electrodes on the transmittance of the otherpixels.

Fifth Embodiment: FIG. 16

Subsequently, a fifth embodiment of the liquid crystal shutter device ofthe invention will be described. FIG. 16 is a partial plan viewcorresponding to FIG. 8 for illustrating an arrangement of electrodesand light shield films in the liquid crystal shutter device. This liquidcrystal shutter device differs from the liquid crystal shutter device ofthe second embodiment in regard only to the structure of counterelectrodes, so that the description will be provided only in thisregard.

In this liquid crystal shutter device, the counter electrodes areprovided in a band-shape separately for each pixel row. Specifically,there are provided an R counter electrode 164, a G counter electrode165, and a B counter electrode 166 corresponding respectively to an Rrow, a G row, and a B row. These counter electrodes are electricallyconnected with each other via an RGB coupling electrode 46 outside theliquid crystal shutter function unit. At the same time, there isprovided an RGB pad electrode 47 in a sealant 33 so that it is possibleto apply electronic signals to respective lacing electrodes therefrom.

In this structure, the facing areas of the lead-out electrodes and thecounter electrodes become larger than those of the first to fourthembodiments mentioned before, nevertheless, it is possible to obtainquite large effectiveness of lowering influence of voltage changes atthe lead-out electrodes on the transmittance of the other pixels ascompared to the conventional device with the counter electrodes providedall over the surface.

Sixth Embodiment and its Modification Examples: FIG. 17 to FIG. 19

Subsequently, a sixth embodiment of the liquid crystal shutter device ofthe invention and its modification examples will be described. FIG. 17is a plan view corresponding to FIG. 1 for illustrating an arrangementof electrodes and light shield films in the liquid crystal shutterdevice, and FIG. 18 and FIG. 19 are plan views corresponding to FIG. 1for illustrating the arrangements of the electrodes and the light shieldfilms for respective modification examples. In these drawings, forportions corresponding to the structure described in the firstembodiment, the same reference numerals are used. In addition, a sealantis shown in FIG. 18 and FIG. 19.

These liquid crystal shutter devices differ from the liquid crystalshutter device of the first embodiment in regard only to the arrangementof the electrodes for connecting black matrixes and counter electrodeswith FPCs, and the structure of the portions related thereto, so thatthe description will be provided only in this regard.

In the liquid crystal shutter device of the embodiment, first, a secondsubstrate 21 projects from a first substrate 1 also on the right side ofthe drawing and, in the projecting portion, a BM pad electrode 50 isalso provided in the right-side projecting portion, the BM pad electrode50 being connected with an R black matrix 25. Incidentally, on the rightside of the drawing, no BM coupling portion 49 is provided. For thecounter electrodes, an RGB pad electrode 47 is also provided on theright side of the drawing. Moreover, there is also provided an RGBcoupling electrode 46 on the right side of the drawing outside theliquid crystal shutter function unit to thereby connect each of thelacing electrodes.

Accordingly, in this liquid crystal shutter device, it is possible toapply electronic signals to the black matrixes and the counterelectrodes respectively via the BM pad electrodes 50 and the RGB padelectrodes 47 from the both left and right sides in the drawing. Then,in order to apply signals from such the both sides, a first FPC 63 isformed to have a different shape from that of the first embodiment sothat it is connected also with the BM pad electrodes 50 and the RGB padelectrodes 47 on both sides in addition to a first driving IC 61,whereby provided with no third FPC.

Additionally, since it is unable to provide a filling hole of liquidcrystal at the same position as of the first embodiment, the fillinghole is provided at the lower right corner of the overlapped portion ofthe first substrate 1 and the second substrate 21 and is closed by aclosing member 34.

In this liquid crystal shutter device, feeding to the black matrixes andthe counter electrodes is carried out from both the sides as mentionedbefore, so that it is possible to prevent voltage drop caused byresistance of the black matrixes and the counter electrodes and, delayin applied waveform caused by capacitance of liquid crystal, allowing toobtain effective voltages extremely close to the applied signals atrespective pixel portions and those portions facing the lead-outelectrodes.

Besides, this is extremely convenient when employing such a connectingstructure as described in the second embodiment in the BM pad electrodes50, since an electrical conductive portion 70 can be formed by fusing athin insulating film 23 by applying pulse voltages via the first FPC 63connected with the BM pad electrodes 50 provided on the right and leftsides.

Other than the above-mentioned structures, the black matrixes and thecounter electrodes may be structured to connect with FPCs as shown inFIG. 18.

In the modification example shown in the drawing, a sealant 133 is ananisotropic conductive sealant (ACS) mixed with conductive particles. Inthe upper right portion and the lower right portion in the drawing,there are provided BM electrodes for ACS 95 for connecting the blackmatrixes with the FPCs, in the overlapped portions with the sealant 133,and there are provided BM electrodes for ACS 96 formed of a transparentconductive film on the first substrate 1 in the positions facing the BMelectrodes for ACS 95. With the conductive particles in the sealant 133,the BM electrodes for ACS 95 on the second substrate 21 and the BMelectrodes for ACS 96 on the first substrate 1 are connected. Besides,the BM electrodes for ACS 96 are connected on the first substrate 1 witha first FPC 63 or a second FPC 64 to thereby electrically connect theblack matrixes with the FPCs also on the right side of the drawing.

Incidentally, a BM pad electrode 50 and an RGB pad electrode 47 on theleft side of the drawing are provided in the same manner as in the firstembodiment, and the counter electrodes are connected with the FPCs onlyvia the RGB pad electrode 47.

According to this structure, the required portion of the secondsubstrate 21 projecting from the first substrate 1 is only of one side,allowing to reduce the size of the liquid crystal shutter device. Also,it is possible to reduce the size of the FPCs to thereby facilitatepressure bonding process for the FPCs. Also in this structure, it isalso possible to apply voltages to the black matrixes from a pluralityof places, so that, as for the black matrixes, the same effect as in thestructure shown in FIG. 17 can be obtained. Particularly, when the BMpad electrode 50 employs the same connecting structure as described inthe second embodiment, it is possible to form the electrical conductiveportion 70 easily by applying pulse voltages via electrodes at pluralpositions, being extremely convenient.

Further, the black matrixes and the counter electrodes may be connectedwith the FPCs as shown in FIG. 19.

In the modification example shown in the drawing, in addition to the BMelectrodes for ACS 95, there are provided counter electrodes for ACS 97for connecting the counter electrodes with the FPCs, in the overlappedportions of an ACS with the sealant 133 and in the upper and lower rightportions in the drawing, and in addition to the BM electrodes for ACS96, there are provided counter electrode connecting electrodes for ACS98 formed of a transparent conductive film in those positions facing thecounter electrodes for ACS 97 on the first substrate 1. With theconductive particles in the sealant 133, the counter electrodes for ACS97 on the second substrate 21 and the counter electrode connectingelectrodes for ACS 98 on the first substrate 1 are connected. Further,the counter electrode connecting electrodes for ACS 98 is connected withthe first FPC 63 or the second FPC 64 on the first substrate 1 tothereby electrically connect the counter electrodes and the FPCs also atthe upper and lower sides in the drawing.

Incidentally, in this liquid crystal shutter device, there is providedno BM pad electrode 50 and RGB pad electrode 47, whereby provided noprojecting portion of the second substrate 21 from the first substrate1.

According to this structure, the second substrate 21 has no projectingportion from the first substrate 1, so that the size of the liquidcrystal shutter device can be made still smaller than that shown in FIG.18. Also, the size of the FPCs can be reduced to thereby facilitate thepressure bonding process for the FPCs. Also, in this structure, it isstill possible to apply voltages from a plurality of places to the blackmatrixes and the counter electrodes, so that the same effect as in thestructure shown in FIG. 17 can be obtained.

Particularly, when the black matrixes are provided with the thininsulating film 23 thereon, it is possible to form the electricalconductive portion 70 by easily fusing the thin insulating film 23 byapplying pulse voltages via the FPCs connecting with the two BMelectrodes for ACS 96, being extremely convenient. Even when there is alarge connection resistance between the counter electrodes and the FPCs,and/or at the ACS portion, it is still possible to lower the connectionresistance by applying the pulse voltages via the FPCs, whereby theresistance portion is electrically broken down.

Seventh Embodiment: FIG. 20

Subsequently, a seventh embodiment of the liquid crystal shutter deviceof the invention will be described. FIG. 20 is a partial sectional viewcorresponding to FIG. 13 for showing a part of the section of the liquidcrystal shutter device. Incidentally, in the drawing, FPCs connectedwith the liquid crystal shutter device are omitted to illustrate, andfor portions corresponding to the first to third embodiments, the samereference numerals are used. Additionally, this liquid crystal shutterdevice differs from the liquid crystal shutter device of the thirdembodiment in regard only to an external light shield member 74 providedtherein, so that the description will be provided only in this regard.

In this liquid crystal shutter device, there is provided the externallight shield member 74 on a first polarizer 71 on a side of a firstsubstrate 1 opposite to a liquid crystal layer 32 in a manner partiallyoverlapped with a black matrix. This external light shield member 74 isprovided for preventing a black matrix space 31 having no black matrixfrom receiving reflected light stream for example by a lens or the like,when the liquid crystal shutter device is used as a liquid crystalshutter of an optical printer. The external light shield member 74therefore has a larger opening than the BM opening 29 corresponding toeach of the pixels, so as not to cover the BM opening 29. Here, oneopening is provided for each row so as to include all the pixels of therow. In addition, the external light shield member 74 is of a thin typeand coats surface of itself with frost black paint to thereby preventreflection on its surface.

Although the black matrix has sufficient effect to prevent a light froma light source by itself, this external light shield member 74 obtainsfurther capability of preventing extra reflection light and the likecoming from other than the light source, allowing a photosensitive paper101 to prevent itself from receiving the reflected light not passingthrough the pixel, so that it is possible to improve quality of imageformed when using the liquid crystal shutter device in the opticalprinter.

Incidentally, the external light shield member 74 may be provided on aside of a second substrate 21 opposite to the liquid crystal side aswell as on both of the first substrate 1 and the second substrate 21.

Eighth Embodiment: FIG. 21 and FIG. 22

Subsequently, an eighth embodiment of the liquid crystal shutter deviceof the invention will be described. FIG. 21 is a partial plan viewcorresponding to FIG. 9 showing a structure of the liquid crystalshutter device, and FIG. 22 is a partial sectional view showing a partof the section taken along line 22—22 in FIG. 21. In these drawings,FPCs connected with the liquid crystal shutter device are omitted toillustrate, and for portions corresponding to the first and secondembodiments, the same reference numerals are used. Additionally, theliquid crystal shutter device of the embodiment is characterized byhaving a plated layer 77 and an external light shield member 74 torealize a light shield function without having any black matrix, so thatthe description will be provided primarily in this regard and fordifferences from the liquid crystal shutter device of the firstembodiment.

First, in this liquid crystal shutter device, differently from the firstembodiment, there is provided no black matrix including R, G, B blackmatrixes 25, 26 and 27, a BM coupling portion 49, and the like. Besides,a counter electrode has a band-shape and separately provided for eachline of respective pixel rows. Specifically, for example, for an R pixelrow 200, there are provided an R1 counter electrode 161 for the firstline pixels, and an R2 counter electrode 162 for the second line pixels.For a G pixel row 300 and a B pixel row 400, the counter electrodes areprovided in the same manner. In total, six band-shaped counterelectrodes are provided, and are electrically connected via an RGBcoupling electrode 46. Additionally, an RGB pad electrode 47 is providedoutside a sealant 33, so that it is allowed to apply electric signals torespective lacing electrodes therefrom.

On the counter electrodes including the RGB coupling electrode 46 andthe RGB pad electrode 47, there is provided the plated layer 77 of ametal plating. Preferably, this plated layer 77 can be formed of, forexample, gold or nickel. For a portion facing each pixel electrode andcorresponding to each pixel, there is provided no plated layer 77 and isformed to be a plated layer opening 78.

Also, as shown in FIG. 22, for a second substrate 21, a thin glass of0.3 mm in thickness is used, and on the opposite side surface of thesecond substrate 21 to a liquid crystal layer 32, the external lightshield member 74 is provided. The reason why external light shieldmember 74 is additionally provided is that the plated layer 77 cannothave enough width in a direction orthogonal to the pixel row since it isprovided on the counter electrode so that it is impossible to haveenough effect independently to shield against the light detouringtherearound from the direction orthogonal to the pixel row. Accordingly,the external light shield member 74 is provided with the openings 74 aat portions corresponding to the respective pixel lines of the pixelrows and is structured to cover all over the second substrate 21 exceptthe portions of the openings 74 a.

In this structure, it is possible to shield periphery of the pixelsagainst light by the external light shield member 74 and the platedlayer 77, eliminating the need of the black matrix. It is also possiblefor the plated layer 77 to reduce the resistance value of the counterelectrodes to thereby lower the influence of the voltage changes at thelead-out electrodes on the voltages to be applied to the liquid crystallayer 32 at the pixel portions via capacitance of the liquid crystallayer 32 and the counter electrodes, so that the influence of thevoltage changes on the transmittances of the pixel portions can belowered.

Ninth Embodiment: FIG. 23 and FIG. 24

Subsequently, a ninth embodiment of the liquid crystal shutter device ofthe invention will be described. FIG. 23 is a partial plan viewcorresponding to FIG. 9 showing a structure of the liquid crystalshutter device, and FIG. 24 is a partial sectional view showing a partof section taken along line 24—24 in FIG. 23. In these drawings, FPCsconnected with the liquid crystal shutter device is omitted toillustrate, and for portions corresponding to the structure of the firstand second embodiments, the same reference numerals are used.Additionally, the liquid crystal shutter device of the embodiment ischaracterized in that a black matrix is made of an insulating material,and accordingly the description will be provided primarily in thisregard and for differences from the liquid crystal shutter device of thefirst embodiment.

First, in this liquid crystal shutter device, as a light shield film,there is provided an insulating black matrix 22 made of resin mixed withblack pigment or the like almost all over the portion surrounded by thesealant 33 on the liquid crystal layer 32 side of the second substrate21, provided that portions facing respective pixel electrodes andcorresponding to pixels are BM openings 29 having no insulating blackmatrix 22. Also, no BM pad electrode 50 is provided for the insulatingblack matrix 22 since the same requires no voltage application.

Further, on the insulating black matrix 22, counter electrodes aredirectly provided without having any insulating film 30 therebetween.The counter electrodes are of a band-shaped and independently providedfor each pixel line of respective pixel rows as in the case of theeighth embodiment.

As with this liquid crystal shutter device, when the insulating blackmatrix 22 is used as the light shield film, no capacity coupling via theliquid crystal layer 32 occurs for the facing portions of the lead-outelectrodes and the light shield films, affecting a display little eventhough the areas of the light shield film are increased.

Incidentally, since there is no need to insulate the counter electrodefrom the insulating black matrix 22, no insulating film 30 is providedhere, however, for the purpose of flattening the steps of the insulatingblack matrix 22, a flattening insulating film may be provided on theinsulating black matrix 22 to provide the counter electrode thereon.

Modification Examples of Respective Embodiments: FIG. 25 to FIG. 27

Subsequently, modification examples of the above-described embodimentswill be described. FIG. 25 is a partial plan view corresponding to FIG.8 showing a structure of the liquid crystal shutter device of the firstembodiment adopting a first modification example, FIG. 26 is a similarpartial plan view showing a configuration of the same adopting a secondmodification example, and FIG. 27 is a partial plan view correspondingto FIG. 2 showing a configuration of the same adopting a thirdmodification example. In these drawings, for portion corresponding tothe structure described in the first embodiment, the same referencenumerals are used. Incidentally, the description will be provided forthose modification examples when adopted in the first embodiment as anexample here, whereas, they may surely be adopted in the otherembodiments.

First, in the first modification example, without providing an RGBcoupling electrode 46 for connecting lacing electrodes corresponding torespective pixel rows, there are provided an R pad electrode 88, a G padelectrode 89, and a B pad electrode 90 for each R, G, B pixel row,together with an R signal connecting portion 135, a G signal connectingportion 136, and a B signal connecting portion 137 respectivelyconnecting therewith to thereby connect counter electrodes, which arecomposed of respective R, G, B lacing electrodes, the pixel counterelectrodes and the like, with a common RGB independent signal controlunit 140. Then, driving signals are applied to the counter electrodesfrom the RGB independent signal control unit 140 via the signalconnecting units 135, 136 and 137, respectively.

As described above, the counter electrodes for the respective pixel rowsmay be electrically connected via external unit such as the RGBindependent signal control unit 140 or the like instead of providing theRGB coupling electrode 46 on a second substrate 21. This makes it alsopossible to obtain the same effect as of the first embodiment providedwith the RGB coupling electrode 46. In this case, on the side of theliquid crystal shutter device, respective R, G, B pad electrodes 88, 89,90 are the connector (connecting means) to electrically connect thecounter electrodes. Similarly, a black matrix being a light shield filmmay have the same structure.

Secondly, in a second modification example, there are provided an Rindependent signal control unit 148, a G independent signal control unit149, and a B independent signal control unit 150 which are connectedwith respective R, G and B signal connecting portion 135, 136 and 137,and whereby connected with an RGB signal control unit 141. Theindependent signal control units 148, 149 and 150 apply independentdriving signals to the counter electrodes of the R, G, B pixel rowsrespectively in response to control signals from the RGB signal controlunit 141. Therefore, the counter electrodes for respective pixel rowsare not connected electrically. In this structure, a driving circuit isrequired for each pixel row, so that the structure is complicated,whereas, the effect of reducing the areas of facing portions of thecounter electrodes and the lead-out electrodes can similarly be obtainedalso in this structure.

Additionally, in this modification example, there are provided a firstsignal connecting portion 151 and a second signal connecting portion 152connected with first and second BM connecting electrodes 58, 59respectively, and a first BM signal control unit 146 and a second BMsignal control unit 147 further connected therewith, so that these areconnected with a BM signal control unit 153 being a light shield filmdriving circuit, whereby driving signals are applied from the BM signalcontrol unit 153 to a BM pad electrode 50 and black matrixestherethrough. The first and second BM signal control units 146, 147 areused to apply voltages to a thin insulating film 23 to cause dielectricbreakdown to thereby form an electrical conductive portion 70 betweenthe first and second BM connecting electrodes 58 and 59, and the BM padelectrode 50.

As described above, a circuit for applying driving signals to the blackmatrixes and a circuit for applying voltages to cause dielectricbreakdown may be provided separately.

Subsequently, in a third modification example, lead-out electrodesconnected with respective pixel electrodes and take-out electrodesconnected with respective pixel counter electrodes are arranged not toface each other.

In the examples shown in FIG. 2 and so on, for instance, an R1 alead-out electrode 15 connected with an R1 a pixel electrode 11 and anR1 a take-out electrode 36 connected with an R1 a pixel counterelectrode 35 are arranged so as to face each other. Preferably, however,the lead-out electrode and the take-out electrode are arranged not toface each other as shown in FIG. 27 from a viewpoint of reducing thefacing areas of the lead-out electrode and the counter electrode, sincethe take-out electrode is also a part of the counter electrode.

Practically, it is presumable that such an arrangement space as in FIG.27 cannot be obtained for displacing the lead-out electrodes and thetake-out electrodes, which face each other in FIG. 2, not to face eachother, because the lead-out electrodes and the take-out electrode eachrequire a certain width to prevent the problems of resistance increase,disconnection, and the like, which are caused in case of an excessivelysmall width, while in the case where the pixel is miniaturized,available wiring width comes to small. Still, even when the take-outelectrodes and the lead-out electrodes have been arranged not to faceeach other, these may overlap each other due to a problem of accuracy inpositioning a first substrate 1 and the second substrate 21.

In view of these considerations, in the previously-describedembodiments, the electrodes are arranged as shown in FIG. 2, whichbrings about sufficient effect of the invention. In practice, however,the arrangement as shown in FIG. 27 is ideal. Accordingly, whenemploying the arrangement shown in FIG. 27, it is preferable that thetake-out electrodes are formed not to overlap the lead-out electrodesled out from the other pixel row even if a kind of positioningdifference is made. (For example, an R1 a take-out electrode 36 of the Rpixel row is arranged not to overlap a G1 a lead-out electrode 18 ledout from a G pixel row.)

Other than described in the above, in the liquid crystal shutter devicesshown in respective embodiments, each of the R, G, B pixel rows isaligned in two lines, yet, the same effect according to the inventioncan be obtained even when each row is aligned in one line.

Also, in the above description, a retardation film 72 is provided on theupper surface of the first substrate 1, however, the same effectaccording to the invention can be obtained in the case where theretardation film 72 is provided on the second substrate 21, or on bothof the first substrate 1 and the second substrate 21. Further, theinvention is applicable to a device provided with no retardation film.

Furthermore, respective characteristics of the above-describedembodiments can be combined.

INDUSTRIAL APPLICABILITY

As has been described, according to the liquid crystal shutter device ofthe invention, counter electrodes are provided independently for eachpixel row to thereby reduce the areas thereof, so that the areas offacing portions of lead-out electrodes and the counter electrodes can bereduced. This makes it possible to lower the influence of signalsapplied to pixel electrodes via the lead-out electrodes ontransmittances of the other pixels via the counter electrodes, and tocontrol the transmittance of each pixel to a desired value, so thatlight irradiation to a photosensitive member can be controlledappropriately. With the use of such a liquid crystal shutter device, itis possible to configure an optical printer capable of forming an imageof high quality without irregular.

1. A liquid crystal shutter device comprising: a liquid crystal cellcomprising a first substrate, a second substrate and liquid crystalsandwiched therebetween; pixel electrodes, which are signal electrodes,and lead-out electrodes provided on said first substrate; counterelectrodes, which are common electrodes facing said pixel electrodes,provided on said second substrate; and a plurality of pixel rowscomprising pixels each formed by an overlapped portion of said pixelelectrode and said counter electrode, each of said pixel rowscorresponding to image formation of a different color, the liquidcrystal shutter device controlling light irradiation to a photosensitivemember continuously and relatively moving in a direction orthogonal tosaid pixel rows, wherein a light shield film is provided separately foreach of said pixel rows and overlaps each of said pixel rows, andwherein openings in said light shield film are provided at portionscorresponding to said pixels.
 2. The liquid crystal shutter deviceaccording to claim 1, wherein said counter electrodes comprise pixelcounter electrodes each corresponding to each of said pixel electrodeand common connecting electrodes for electrically connecting said pixelcounter electrodes.
 3. The liquid crystal shutter device according toclaim 2, wherein said common connecting electrodes comprise lacingelectrodes provided alongside said pixel rows and take-out electrodesfor connecting said pixel counter electrodes and said lacing electrodes.4. The liquid crystal shutter device according to claim 3, wherein, inan overlapped portion of said lead-out electrode and said lacingelectrode, either of said lead-out electrode or said lacing electrode ismade small in line width as compared to the remaining portions thereof.5. The liquid crystal shutter device according to claim 2, wherein saidpixel counter electrode is formed in an almost same shape as of saidpixel electrode.
 6. The liquid crystal shutter device according to claim1, wherein pixels composing said pixel rows are aligned in two lines foreach pixel row at same pitches as of a pixel size in an aligningdirection, the pixels of one of the two lines and the pixels of theother line being arranged at positions misaligning by one pixel size inrespective aligning directions.
 7. The liquid crystal shutter deviceaccording to claim 6, wherein said common connecting electrode comprisesa lacing electrode provided alongside said pixel rows and a take-outelectrode for connecting said pixel counter electrodes and said lacingelectrodes, and wherein said lacing electrodes are provided on bothsides of said pixel counter electrodes aligned in two lines and saidtake-out electrodes taken out from said pixel counter electrodes alignedin two lines are connected with said lacing electrode on correspondingside, respectively.
 8. The liquid crystal shutter device according toclaim 6, wherein said common connecting electrode comprises a lacingelectrode provided alongside said pixel rows and a take-out electrodefor connecting said pixel counter electrodes and said lacing electrodes,and wherein said lacing electrodes are provided on one side of the pixelcounter electrodes aligned in two lines, and said take-out electrodesconnect in common respective pair of pixel counter electrodes composingsaid pixel counter electrodes aligned in two lines and also connect saidpair of pixel counter electrodes with said lacing electrodes.
 9. Theliquid crystal shutter device according to claim 1, wherein said pixelscomposing said pixel rows are aligned in two lines for each pixel row atsame pitches as of a pixel size in an aligning direction, the pixels ofone of the two lines and the pixels of the other line being arranged atpositions misaligning with each other by one pixel size in respectivealigning directions, and wherein each of said counter electrodes isprovided in an one-band shape for said pixel electrodes composing saidpixels aligned in two lines.
 10. The liquid crystal shutter deviceaccording to claim 1, wherein said pixels composing said pixel rows arealigned in two lines for each pixel row at same pitches as of a pixelsize in an aligning direction, the pixels of one of the two lines andthe pixels of the other line being arranged at positions misaligningwith each other by one pixel size in respective aligning directions, andwherein each of said counter electrodes are provided in a band shape forsaid pixel electrodes composing the pixels aligned in two lines,separately for each line.
 11. The liquid crystal shutter deviceaccording to claim 1, wherein three pixel rows are provided as saidplurality of pixel rows.
 12. The liquid crystal shutter device accordingto claim 11, wherein the three pixel rows are pixel rows correspondingto respective colors of red (R), green (G), and blue (B).
 13. The liquidcrystal shutter device according to claim 11, wherein, in outside twopixel rows out of the three pixel rows, said counter electrode iscomprised of pixel counter electrodes each corresponding to each of saidpixel electrodes and common connecting electrodes for electricallyconnecting said pixel counter electrodes, and in a center pixel row,said counter electrode is formed in a band shape so as to face saidpixel electrodes of corresponding pixel row.
 14. The liquid crystalshutter device according to claim 1, further comprising a metal-platedlayer for portions of said counter electrodes except those portionsfacing said pixel electrodes.
 15. The liquid crystal shutter deviceaccording to claim 1, further comprising a light shield film connectorfor electrically connecting said light shield films separately providedfor each of said pixel rows.
 16. The liquid crystal shutter deviceaccording to claim 1, further comprising a pad electrode provided onsaid second substrate for supplying said light shield films withelectric signals.
 17. The liquid crystal shutter device according toclaim 16, wherein comprising a connecting electrode facing said padelectrode via the insulating film is provided on said second substrate.18. The liquid crystal shutter device according to claim 17, wherein aconductive area is formed in the insulating film between said padelectrode and said connecting electrode.
 19. The liquid crystal shutterdevice according to claim 18, further comprising a light shield filmdriving circuit for supplying said connecting electrode with a lightshield film driving signal.
 20. The liquid crystal shutter deviceaccording to claim 19, wherein said light shield film driving circuit isa circuit for supplying said pad electrode with the light shield filmdriving signal from said connecting electrode via the conductive area.21. The liquid crystal shutter device according to claim 20, wherein thelight shield film driving signal is a signal having a medium voltage ofa voltage range being applied to said liquid crystal by said pixelelectrodes and said counter electrodes.
 22. The liquid crystal shutterdevice according to claim 17, further comprising a light shield filmdriving circuit for supplying said connecting electrode with a lightshield film driving signal, wherein said light shield film drivingcircuit is a circuit for supplying said pad electrode with an AC lightshield film driving signal from said connecting electrode via theinsulating film.
 23. The liquid crystal shutter device according toclaim 22, wherein the light shield film driving signal is a signal acenter voltage of which is a medium voltage of the voltage range beingapplied to said liquid crystal by said pixel electrodes and said counterelectrodes.
 24. The liquid crystal shutter device according to claim 1,further comprising an external light shield member provided on a side ofsaid first substrate or said second substrate opposite to said liquidcrystal.
 25. The liquid crystal shutter device according to claim 1,wherein said light shield film is a metallic light shield film andprovided on said second substrate, with an insulating film between saidcounter electrodes and said light shield film.
 26. The liquid crystalshutter device according to claim 25, wherein said counter electrodesare separately provided for each of said pixel rows.
 27. The liquidcrystal shutter device according to claim 26, further comprising aconnector for electrically connecting said counter electrodes for eachof said pixel rows.
 28. The liquid crystal shutter device according toclaim 27, wherein said connector is provided outside a liquid crystalshutter function portion in which said pixel rows are arranged.